US5537993A - Gas ratio control device for anestesia apparatus - Google Patents
Gas ratio control device for anestesia apparatus Download PDFInfo
- Publication number
- US5537993A US5537993A US08/524,609 US52460995A US5537993A US 5537993 A US5537993 A US 5537993A US 52460995 A US52460995 A US 52460995A US 5537993 A US5537993 A US 5537993A
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- US
- United States
- Prior art keywords
- chamber
- remainder
- slide
- gas
- pressure
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
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Classifications
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
- G05D11/00—Control of flow ratio
- G05D11/006—Control of flow ratio involving a first fluid acting on the feeding of a second fluid
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
- A61M16/10—Preparation of respiratory gases or vapours
- A61M16/104—Preparation of respiratory gases or vapours specially adapted for anaesthetics
Definitions
- the present invention pertains to a gas ratio control device for anesthesia apparatus comprising an anesthetic gas feed line, which has, in a series-connected arrangement, a control valve with an inlet chamber and with an outlet chamber, an anesthetic gas-adjusting valve and a first measuring resistance, as well as an oxygen feed line, which has, in a series-connected arrangement, an oxygen-adjusting valve and a second measuring resistance, with a proportional element, which has a first pressure chamber, which receives the dynamic pressure from the first measuring resistance and is limited by a first diaphragm, and a second pressure chamber, which receives the dynamic pressure from the second measuring resistance and is limited by a second diaphragm, a slide, which connects the diaphragms, actuates the control valve and is passed through at least two chambers divided by a projection, whose chamber volume is influenced by the deflection of the diaphragms.
- a gas ratio control device of this type has become known from DE 41 11 139 A1 (corresponding to U.S. Pat. No. 5,335,652; U.S. Pat. No. 5,335,652 is hereby incorporated by reference).
- Anesthetic gas, laughing gas in this case is sent in the prior-art gas ratio control device into an inlet chamber of a control valve via an anesthetic gas feed line, and then to a fresh gas outlet from an outlet chamber of the control vane via an anesthetic gas-adjusting valve and a first measuring resistance.
- Oxygen is also sent as an additional gas via an oxygen feed line, an oxygen-adjusting valve and a second measuring resistance to the fresh gas outlet, where the two gas flows merge.
- Dynamic pressures which are sent as a differential pressure to a proportional element, are generated by the gas flows at the measuring resistances, and the proportional element controls the control valve in the anesthetic gas feed line according to the value of the difference between the two dynamic pressures so that the anesthetic gas flow, i.e., the flow of laughing gas, does not exceed a certain value in relation to the flow of oxygen.
- the proportional element has a first pressure chamber to receive the dynamic pressure generated at the first measuring resistance, and a second pressure chamber to receive the dynamic pressure generated at the second measuring resistance.
- a diaphragm which is deflected in proportion to the pressure prevailing in the pressure chambers, is located in each pressure chamber.
- a ball seat vane in the control valve is actuated via a rod connecting the diaphragms, as a result of which the flow of anesthetic gas from the inlet chamber into the outlet chamber changes.
- a pressure-reducing vane with a closing piston which is connected to a control piston located in a control cylinder and to a damping piston accommodated in a damping cylinder, has been known from DE 32 19 552 A1.
- a control pressure actuating the control piston is admitted to the control cylinder.
- the damping piston divides the damping cylinder into an upper cylinder space and a lower cylinder space, which are connected to one another via a laminar throttle.
- the sensitivity of the closing piston to suddenly occurring pressure shocks is reduced by the throttled gas exchange between the two cylinder spaces on both sides of the damping cylinder.
- the primary object of the present invention is to improve a gas ratio control device such that a flow-proportional addition of the anesthetic gas to the fresh gas is possible even at low oxygen flow rate values.
- outlet chamber and the first pressure chamber are connected to one another in one piece in terms of flow; that the anesthetic gas-adjusting valve is arranged in front of the inlet chamber in the direction of flow; and that a flow resistance throttling the exchange of gas between the chambers is provided.
- the advantage of the present invention is essentially that both opening and closing forces are minimized due to the changed connections of the control valve to the anesthetic gas-adjusting valve in front of the inlet chamber of the control valve and to the elimination of a sealing seat, on the one hand, and that an effective damping of the slide actuating the control valve is achieved by the measuring resistance between the chambers limited by the diaphragms, on the other hand.
- This damping operates independently from the control pressures deflecting the diaphragms.
- the measuring resistance may be designed as a throttle bore within the projection, and the slide is passed through the projection with a clearance fit, so that most of the gas exchange takes place via the throttle bore.
- At least one of the chambers is advantageously connected to the environment via an additional flow resistance, so that an exchange of gas between the chamber and the environment is possible. It is also possible for both chambers to be connected to the environment via flow resistances. By adjusting the individual flow resistances, a good response behavior of the proportional element can be set at small pressure differences between the pressure chambers.
- the projection between the chambers preferably has a hole accommodating the slide, and the diameter of the hole and the diameter of the slide are selected to be such that a gas-carrying annular gap, which acts as a flow resistance between the chambers, is formed.
- the slide advantageously is comprised of a first slide section and a second slide section, wherein the first slide section has two pressing pieces, which are in contact with the diaphragms and are connected to one another via a rod guided in a hole.
- the second slide section is a plunger, which is displaceable in a clearance fit and actuates the control valve.
- the diaphragms are made of a flaccid, flexible elastomer and lie displaceably on the pressing pieces. Warping, which may occur between the diaphragms and the slide sections during mounting, is thus avoided, and the friction of the slide sections within the hole or the clearance-fit is further reduced compared with a rigid connection between the slide and the diaphragms.
- FIG. 1 is a schematic view of a first gas ratio control device according to the state of the art
- FIG. 2 is a schematic view of a second gas ratio control device according to the present invention.
- FIG. 3 is a schematic view of a third gas ratio control device according to the present invention.
- an anesthetic gas (N 2 O) feed line 1 and an oxygen feed line 2 are united together in a fresh gas outlet 3.
- the fresh gas outlet 3 is followed by an anesthetic gas evaporator, which is not shown in FIG. 1.
- the anesthetic gas feed line 1 contains a first pressure reducer 4, an anesthetic gas-adjusting valve 5, a first measuring resistance 6, as well as a first flow-measuring tube 7.
- a second pressure reducer 8, an oxygen-adjusting valve 9, a second measuring resistance 10, and a second flow-measuring tube 11 are provided in the same manner in the oxygen feed line 2.
- the first proportional element 13 consists of a first diaphragm 132 and a second diaphragm 131, which are connected to one another via a slide 133.
- the diaphragms 132, 131 limit a first pressure chamber 135, to which an anesthetic gas dynamic pressure picked up (present) in front of the first measuring resistance 6 is admitted, and a second pressure chamber 134, on which an oxygen dynamic pressure picked up (present) in front of the second measuring resistance 10 acts.
- the control valve 12 consists of a spring-loaded ball seat valve 121, which is arranged between an inlet chamber 122 and an outlet chamber 123 and can be opened or closed by the slide 133.
- the ball of the ball seat valve 121 is pressed into the valve seat by a spring 15 and a pressure difference acting between the inlet chamber 122 and the outlet chamber 123.
- the force of the spring 15, the pressing force resulting from the pressure difference between the inlet chamber 122 and the outlet chamber 123, which acts on the ball of the ball seat valve 121, as well as the frictional force caused by the sealing seat 14, must be overcome. Since the sealing seat 14 usually consists of an elastomer, which is deformed under the actually prevailing pressure, the frictional force generally depends on the pressure.
- the flow of anesthetic gas in the anesthetic gas feed line 1 can be throttled or even shut off completely with the ball seat valve 121.
- the ball seat valve 121 is, e.g., in the shut-off position when the oxygen dynamic pressure has dropped and the second diaphragm 131 is deflected to the left together with the slide 133.
- the feed of anesthetic gas is controlled by the interaction between the oxygen dynamic pressure and the anesthetic gas dynamic pressure, and it is ensured that the minimum oxygen concentration cannot drop below, e.g., 25 vol.%.
- FIG. 2 shows a gas ratio control device with a second proportional element generally designated 430 according to the present invention.
- the anesthetic gas-adjusting valve 405 of the invention is arranged in front of the inlet chamber 422 in terms of flow, and the outlet chamber 423 as well as the first pressure chamber 435 are connected to one another in one piece, as a result of which the sealing seat 14, which is part of the device shown in FIG. 1, and consequently the frictional force at the sealing seat, are eliminated.
- the dynamic pressure which has decreased at the first measuring resistance 406 and is only in the mbar range, prevails in the outlet chamber 423.
- the pressure in the inlet chamber 422 also decreases due to the throttling action of the anesthetic gas-adjusting valve 405, so that, on the whole, only a markedly weaker resulting pressing force acts on the ball of the ball seat valve 421 compared with the arrangement according to FIG. 1.
- the space located between the diaphragms 431, 432 is divided into a first chamber 436 and a second chamber 437, wherein the chambers 436, 437 are connected to one another via an annular gap 438.
- the annular gap 438 is designed as a flow resistance between the chambers 436, 437 and is formed by the difference in diameters between a hole 439 in a projection (projections defining wall portions) 440 within the second proportional element 430 and the slide 433, which is guided by the hole 439.
- the projection 440 separates the first chamber 436 from the second chamber 437.
- the first chamber 436 is connected to the environment via a first outlet 441 and a first flow resistance 442, and the second chamber 437 has a corresponding second outlet 443 with a second flow resistance 444.
- the axial movement of the slide 433 is damped by the exchange of gas between the chambers 436, 437 via the annular gap 438, on the one hand, and by the exchange of gas between the chambers 436, 437 via the flow resistances 442, 444 with the environment, on the other hand.
- the dynamic behavior of the second proportional valve 430 can be optimized to a new value during the adjusting.
- the diaphragms 431, 432 are directly connected to the one-piece slide 433 in the second proportional element 430 shown in FIG. 2.
- FIG. 3 shows a third proportional element generally designated 445, which has additional advantageous improvements compared with the second proportional element 430.
- Identical components are designated by the same reference numbers as in FIG. 2.
- the difference from FIG. 2 is that the slide 433 is divided into a first slide section 446 and a second slide section 447.
- the first slide section 446 is comprised of two disk-shaped pressing pieces 448, 449, which are connected to one another by means of a rod 450 guided by a hole 439.
- the diameter of the hole 439 and that of the rod 450 are selected to be such that the annular gap 438 forming the flow resistance is formed.
- the diaphragms 431, 432 consist of a flaccid, flexible elastomer, lie flat on the pressing pieces 448, 449, and are displaceable in relation thereto.
- the second slide section 447 is a plunger 452 which is guided in a clearance fit 451 and has a pressing piece 453 supported by the second diaphragm 432.
- the plunger 453 is supported by means of a compression spring 454 in relation to the housing of the third proportional element 445.
- Frictional forces, especially of the rod 450 within the hole 439, are further reduced by the slide being divided into the first slide section 446 and the second slide section 447, because the diaphragms (431, 432) are displaceable in relation to the pressing pieces 448, 449, as a result of which no mechanical warping can occur between the pressing pieces 448, 449 and the diaphragms 431, 432.
- assembly is substantially simplified, because the slide no longer needs to be mechanically connected to the diaphragms 431, 432, unlike in FIGS. 1 and 2.
- the third proportional element 445 has connections (a, b, c), which are connected to the corresponding lines (a,b,c) of the connection diagram in FIG. 2.
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- Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Biomedical Technology (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Physics & Mathematics (AREA)
- Emergency Medicine (AREA)
- Pulmonology (AREA)
- Anesthesiology (AREA)
- Physics & Mathematics (AREA)
- Heart & Thoracic Surgery (AREA)
- Hematology (AREA)
- Automation & Control Theory (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
- Measuring Volume Flow (AREA)
- Flow Control (AREA)
Abstract
Description
Claims (5)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE4437207A DE4437207C1 (en) | 1994-10-18 | 1994-10-18 | Gas-flow ratio regulation of anaesthetic gases |
DE4437207.8 | 1994-10-18 |
Publications (1)
Publication Number | Publication Date |
---|---|
US5537993A true US5537993A (en) | 1996-07-23 |
Family
ID=6531071
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US08/524,609 Expired - Fee Related US5537993A (en) | 1994-10-18 | 1995-09-07 | Gas ratio control device for anestesia apparatus |
Country Status (3)
Country | Link |
---|---|
US (1) | US5537993A (en) |
EP (1) | EP0707863B1 (en) |
DE (2) | DE4437207C1 (en) |
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6428500B1 (en) * | 1997-05-07 | 2002-08-06 | Saturnus Ag | Adhesion prevention and an endoscopic insufflation system therefor |
EP1273317A1 (en) * | 2001-07-04 | 2003-01-08 | Siemens-Elema AB | Fluid flow regulation system |
US20050010164A1 (en) * | 2003-04-24 | 2005-01-13 | Mantell Robert R. | Mixed-gas insufflation system |
US20050137529A1 (en) * | 2003-10-07 | 2005-06-23 | Mantell Robert R. | System and method for delivering a substance to a body cavity |
US20060081244A1 (en) * | 2004-10-19 | 2006-04-20 | Thomas Bouillon | Anesthesia device, system and method |
US20080033344A1 (en) * | 2006-08-04 | 2008-02-07 | Mantell Robert R | In-Dwelling Port For Access Into A Body |
US20100326069A1 (en) * | 2009-06-29 | 2010-12-30 | Lightsail Energy Inc. | Compressed air energy storage system utilizing two-phase flow to facilitate heat exchange |
US7914517B2 (en) | 2003-10-31 | 2011-03-29 | Trudell Medical International | System and method for manipulating a catheter for delivering a substance to a body cavity |
US8257297B2 (en) | 2002-10-28 | 2012-09-04 | Northgate Technologies, Inc. | Dual-capacity insufflator tube |
US8584693B2 (en) | 2010-08-13 | 2013-11-19 | Linde Aktiengesellschaft | Device for monitoring gas concentration and method using the device |
US9572595B1 (en) | 2014-03-05 | 2017-02-21 | Northgate Technologies Inc. | In-dwelling port for access into a body |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2196885A1 (en) * | 2008-12-15 | 2010-06-16 | Z & H Wassertechnik GmbH | Method and device for blending liquids with different characteristics as control variables |
Citations (12)
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US3047210A (en) * | 1958-12-26 | 1962-07-31 | United Aircraft Corp | Compressor surge control |
US4015617A (en) * | 1975-03-25 | 1977-04-05 | Fraser Sweatman, Inc. | Analgesic apparatus |
US4191952A (en) * | 1978-08-25 | 1980-03-04 | N.A.D., Inc. | Low oxygen flow alarm for anesthesia systems |
US4328823A (en) * | 1980-05-14 | 1982-05-11 | N.A.D. Inc. | Oxygen flow ratio controller for anesthesia apparatus |
DE3219552A1 (en) * | 1982-05-25 | 1983-12-01 | Johannes Erhard, H. Waldenmaier Erben Süddeutsche Armaturenfabrik GmbH & Co, 7920 Heidenheim | Pressure-reducing valve |
US4442856A (en) * | 1981-08-18 | 1984-04-17 | Puritan-Bennett | Oxygen regulator and alarm system for an anesthesia machine |
FR2548908A1 (en) * | 1983-06-23 | 1985-01-18 | Atlantique Ing Tech | Gas mixer for anaesthesia and resuscitation apparatus |
GB2148721A (en) * | 1983-10-25 | 1985-06-05 | Citizen Watch Co Ltd | Gas flow control system for an anesthesia apparatus |
US4555952A (en) * | 1984-06-08 | 1985-12-03 | Borg-Warner Corporation | Differential pressure sensor |
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US5411019A (en) * | 1993-11-03 | 1995-05-02 | North American Drager | Integrated oxygen ratio controller |
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US3762430A (en) * | 1971-04-30 | 1973-10-02 | Isotopes Inc | Differential pressure regulator |
US3739799A (en) * | 1971-09-07 | 1973-06-19 | Fraser Sweatman | Continuous flow anesthesia apparatus |
US3817264A (en) * | 1973-02-14 | 1974-06-18 | Precision Control Prod Corp | Valve |
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US4237813A (en) * | 1977-07-22 | 1980-12-09 | Howison Ronald G | Warning and protective device |
GB2076661B (en) * | 1980-05-30 | 1984-08-15 | Chubb Panorama | Valves and breathing apparatus incorporating such valves |
AU543291B2 (en) * | 1981-01-06 | 1985-04-18 | Medishield Corp. Ltd. | Gas switching device |
FR2549979A1 (en) * | 1983-07-28 | 1985-02-01 | Robert Et Carriere Draeger | Safety flow meter for anaesthesia. |
US5159924A (en) * | 1990-10-03 | 1992-11-03 | Cegielski Michael J | Method and apparatus for selectively mixing gases |
-
1994
- 1994-10-18 DE DE4437207A patent/DE4437207C1/en not_active Expired - Fee Related
-
1995
- 1995-09-07 US US08/524,609 patent/US5537993A/en not_active Expired - Fee Related
- 1995-09-22 EP EP95114944A patent/EP0707863B1/en not_active Expired - Lifetime
- 1995-09-22 DE DE59508887T patent/DE59508887D1/en not_active Expired - Lifetime
Patent Citations (14)
Publication number | Priority date | Publication date | Assignee | Title |
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US3047210A (en) * | 1958-12-26 | 1962-07-31 | United Aircraft Corp | Compressor surge control |
US4015617A (en) * | 1975-03-25 | 1977-04-05 | Fraser Sweatman, Inc. | Analgesic apparatus |
US4191952A (en) * | 1978-08-25 | 1980-03-04 | N.A.D., Inc. | Low oxygen flow alarm for anesthesia systems |
US4328823A (en) * | 1980-05-14 | 1982-05-11 | N.A.D. Inc. | Oxygen flow ratio controller for anesthesia apparatus |
US4442856A (en) * | 1981-08-18 | 1984-04-17 | Puritan-Bennett | Oxygen regulator and alarm system for an anesthesia machine |
DE3219552A1 (en) * | 1982-05-25 | 1983-12-01 | Johannes Erhard, H. Waldenmaier Erben Süddeutsche Armaturenfabrik GmbH & Co, 7920 Heidenheim | Pressure-reducing valve |
FR2548908A1 (en) * | 1983-06-23 | 1985-01-18 | Atlantique Ing Tech | Gas mixer for anaesthesia and resuscitation apparatus |
GB2148721A (en) * | 1983-10-25 | 1985-06-05 | Citizen Watch Co Ltd | Gas flow control system for an anesthesia apparatus |
US4555952A (en) * | 1984-06-08 | 1985-12-03 | Borg-Warner Corporation | Differential pressure sensor |
DE3810745A1 (en) * | 1988-03-30 | 1989-10-12 | Draegerwerk Ag | GAS RATIO CONTROL DEVICE FOR NARCOSIS DEVICES |
US4972831A (en) * | 1988-03-30 | 1990-11-27 | Dragerwerk Aktiengesellschaft | Gas ratio controlling device for anesthetic appliances |
DE4111139A1 (en) * | 1991-04-06 | 1992-10-08 | Draegerwerk Ag | GAS RATIO CONTROL DEVICE FOR NARCOSIS DEVICES |
US5335652A (en) * | 1991-04-06 | 1994-08-09 | Dragerwerk Aktiengesellschaft | Gas ratio control device for anesthetic apparatus |
US5411019A (en) * | 1993-11-03 | 1995-05-02 | North American Drager | Integrated oxygen ratio controller |
Cited By (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6428500B1 (en) * | 1997-05-07 | 2002-08-06 | Saturnus Ag | Adhesion prevention and an endoscopic insufflation system therefor |
EP1273317A1 (en) * | 2001-07-04 | 2003-01-08 | Siemens-Elema AB | Fluid flow regulation system |
US6874503B2 (en) | 2001-07-04 | 2005-04-05 | Maquet Critical Care Ab | Fluid flow regulation system |
US8257297B2 (en) | 2002-10-28 | 2012-09-04 | Northgate Technologies, Inc. | Dual-capacity insufflator tube |
US7654975B2 (en) | 2003-04-24 | 2010-02-02 | Northgate Technologies, Inc. | Mixed-gas insufflation system |
US20050010164A1 (en) * | 2003-04-24 | 2005-01-13 | Mantell Robert R. | Mixed-gas insufflation system |
US20050137529A1 (en) * | 2003-10-07 | 2005-06-23 | Mantell Robert R. | System and method for delivering a substance to a body cavity |
US7704223B2 (en) | 2003-10-07 | 2010-04-27 | Northgate Technologies Inc. | System and method for delivering a substance to a body cavity |
US20100268153A1 (en) * | 2003-10-07 | 2010-10-21 | Northgate Technologies Inc. | System and method for delivering a substance to a body cavity |
US8105267B2 (en) | 2003-10-07 | 2012-01-31 | Northgate Technologies Inc. | System and method for delivering a substance to a body cavity |
US7914517B2 (en) | 2003-10-31 | 2011-03-29 | Trudell Medical International | System and method for manipulating a catheter for delivering a substance to a body cavity |
US7556036B2 (en) * | 2004-10-19 | 2009-07-07 | Dräger Medical AG & Co. KG | Anesthesia device, system and method |
US20060081244A1 (en) * | 2004-10-19 | 2006-04-20 | Thomas Bouillon | Anesthesia device, system and method |
US20080033344A1 (en) * | 2006-08-04 | 2008-02-07 | Mantell Robert R | In-Dwelling Port For Access Into A Body |
US8663271B2 (en) | 2006-08-04 | 2014-03-04 | Northgate Technologies, Inc. | In-dwelling port for access into a body |
US9345870B2 (en) | 2006-08-04 | 2016-05-24 | Northgate Technologies Inc. | In-dwelling port for access into a body |
US20100326069A1 (en) * | 2009-06-29 | 2010-12-30 | Lightsail Energy Inc. | Compressed air energy storage system utilizing two-phase flow to facilitate heat exchange |
US8584693B2 (en) | 2010-08-13 | 2013-11-19 | Linde Aktiengesellschaft | Device for monitoring gas concentration and method using the device |
US9572595B1 (en) | 2014-03-05 | 2017-02-21 | Northgate Technologies Inc. | In-dwelling port for access into a body |
Also Published As
Publication number | Publication date |
---|---|
EP0707863B1 (en) | 2000-12-06 |
DE4437207C1 (en) | 1996-01-04 |
EP0707863A1 (en) | 1996-04-24 |
DE59508887D1 (en) | 2001-01-11 |
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